Beta-adrenergic drugs and risk of Parkinson's disease: A systematic review and meta-analysis.

BACKGROUND:Parkinson's Disease (PD) is a neurodegenerative disorder manifested by rest tremor, rigidity, bradykinesia, and postural instability. Recent pharmaco-epidemiological studies evaluating beta-adrenergic drug use and risk of PD have reported conflicting findings. OBJECTIVES:This systematic review and meta-analyses evaluate the association between beta-adrenergic (agonists and antagonists) drugs' use and PD. METHODS:An electronic literature search of eight databases was performed from inception to July 2021 to identify pharmaco-epidemiological studies (case-control and cohort) reporting the risk of PD in beta-adrenergic users compared to non-users. We used the generic inverse variance method and RevMan (5.3.5) to estimate pooled adjusted risk ratios (aRRs) of PD using a random-effects model. RESULTS:Of 3168 records, 15 studies (10 case-control; five cohort) with 6508,877 participants, including 87,011 PD cases, were included. In the pooled analysis (n = 10) including any beta-antagonist users, compared with non-users, the aRR for PD was 1.19 (CI: 1.05,1.35); for any beta-agonist users (n = 8) aRR for PD was 0.87 (CI: 0.78,0.97). Propranolol users had a significantly increased risk of PD (aRR:1.91; CI:1.20,3.06), whereas salbutamol use was associated with reduced risk of PD (aRR:0.95; CI:0.92,0.99). Significant heterogeneity (I2 >87%) was observed, but the majority (n = 13) of the studies were of high quality, based on the JBI tool. CONCLUSIONS:Beta-antagonist use was associated with a modestly increased risk of PD, whereas beta-agonist use was associated with a modest decreased risk of PD. Future epidemiological studies should address the issues of protopathic bias and indirect association using appropriate epidemiological methods.